to them,αὐτοῖς(autois)Personal / Possessive Pronoun - Dative Masculine 3rd Person PluralStrong's Greek 846: He, she, it, they, them, same. From the particle au; the reflexive pronoun self, used of the third person, and of the other persons.

to the extent thatκαθὼς(kathōs)AdverbStrong's Greek 2531: According to the manner in which, in the degree that, just as, as. From kata and hos; just as, that.

they couldἠδύναντο(ēdynanto)Verb - Imperfect Indicative Middle or Passive - 3rd Person PluralStrong's Greek 1410: (a) I am powerful, have (the) power, (b) I am able, I can. Of uncertain affinity; to be able or possible.

(33-34) And with many such parables.--See Notes on Matthew 13:34-35. St. Mark's omission of the reference to Psalm 78:2, and his addition of "as they were able to hear it," are, each of them, characteristic. It may be noted that the "many such parables" of St. Mark imply something like the series which we find in St. Matthew.

Verses 33, 34. - Withmany such parables; such, that is, as he had just been delivering - plain and simple illustrations which all might understand; not abstruse and difficult similitudes, but sufficiently plain for them to perceive that there was heavenly and Divine truth lying hidden beneath them, so that they might be drawn onwards through that which they did understand, to search into something hidden beneath it, which at present they did not know. But privately to his own disciples heexpounded (ἐπέλυε) all things. This word (ἐπιλύω) occurs nowhere else in the Gospels. But it does occur in St. Peter's second Epistle (2 Peter 1:20), "No Scripture is of any private (ἐπιλύσεως) exposition, or interpretation." This suggests a connection between St. Mark's Gospel and that Epistle, and may be accepted as an auxiliary evidence, however small, as to the genuineness of the Epistle.